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FILE_LICENCE ( GPL2_OR_LATER )
.text
.arch i386
.section ".prefix", "awx", @progbits
.code16
.org 0
movw $load_image, %bp
jmp find_active_partition
#include "bootpart.S"
load_image:
/* Get disk geometry */
pushal
pushw %es
movb $0x08, %ah
int $0x13
jc load_failed
movb %cl, max_sector
movb %dh, max_head
popw %es
popal
1: /* Read to end of current track */
movb %cl, %al
negb %al
addb max_sector, %al
incb %al
andb $0x3f, %al
movzbl %al, %eax
call *read_sectors
jc load_failed
/* Update %es */
movw %es, %bx
shll $5, %eax
addw %ax, %bx
movw %bx, %es
shrl $5, %eax
/* Update LBA address */
addl %eax, %edi
adcl $0, %esi
/* Update CHS address */
andb $0xc0, %cl
orb $0x01, %cl
incb %dh
cmpb max_head, %dh
jbe 2f
xorb %dh, %dh
incb %ch
jnc 2f
addb $0xc0, %cl
2:
/* Loop until whole image is read */
subl %eax, load_length
ja 1b
ljmp $BOOT_SEG, $start_image
max_sector:
.byte 0
max_head:
.byte 0
load_length:
.long 0
.section ".zinfo.fixup", "a", @progbits /* Compressor fixups */
.ascii "ADDL"
.long load_length
.long 512
.long 0
.previous
load_failed:
movw $10f, %si
jmp boot_error
10: .asciz "Could not load gPXE\r\n"
.org 510
.byte 0x55, 0xaa
start_image:
/* Install gPXE */
call install
/* Set up real-mode stack */
movw %bx, %ss
movw $_estack16, %sp
/* Jump to .text16 segment */
pushw %ax
pushw $1f
lret
.section ".text16", "awx", @progbits
1:
pushl $main
pushw %cs
call prot_call
popl %ecx /* discard */
/* Uninstall gPXE */
call uninstall
/* Boot next device */
int $0x18
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